• ## CHAPTER 3: MULTIPLY BY 2-DIGIT NUMBERS

 In Chapter 3 students will:   Use place value and multiplication properties to multiply 2-digit numbers by a 2-digit tens Estimate products by rounding or using compatible numbers Use place value, area models, and partial products to multiply 2-digits by 2-digits Use regrouping to multiply 2-digits by 2-digits Solve multistep multiplication word problems Vocabulary: Associative Property of Multiplication - the property that states that you can group factors in different ways and get the same product  ex: (6x10)x10 = 6x(10x10) factor – a number that is multiplied by another number to find a product product – the answer to a multiplication problem compatible numbers - numbers that are easy to compute mentally and work well together  ex: 25 & 4 partial product – a method of multiplying in which the ones, tens, hundreds, and so on are multiplied separately and then the products are added together estimate – a number close to an exact amount round – to replace a number with another number that tells about  how many or how much; 39 rounds to 40, 128 rounds to 100 Chapter 3 Standards:  Operations and Algebraic Thinking;  Number and Operations in Base TenUse the four operations with whole numbers to solve problems; CC.4.OA.3    Solve multistep word problems posed with whole numbers and having whole-number answers using the four operations, including problems in which remainders must be interpreted.  Represent these problems using equations with a letter standing for the unknown quantity.  Assess the reasonableness of answers using mental computation and estimation strategies including rounding.Use place value understanding and properties of operations to perform multi-digit arithmetic;  CC.4.NBT.5    Multiply a whole number up to four digits by a one-digit whole number, and multiply two two-digit numbers, using strategies based on place value and the properties of operations.  Illustrate and explain the calculation by using equations, rectangular arrays, and/or area models.
• Chapter 3 videos:

Lesson 3.1  Multiply by Tens (CC.4.NBT.5)
Lesson 3.2  Estimate Products (CC.4.NBT.5)
Lesson 3.3  Area Models and Partial Products (CC.4.NBT.5)
Lesson 3.4  Multiply Using Partial Products (CC.4.NBT.5)
Lesson 3.5  Multiply with Regrouping (CC.4.NBT.5)
Lesson 3.6  Choose a Multiplication Method (CC.4.NBT.5)
Lesson 3.7  Problem Solving: Multiply 2-Digit Numbers (CC.4.OA.3)